1. Field of the Invention
This invention relates to a coaxial line assembly for transmitting a high frequency signal and, more particularly, relates to such a coaxial line assembly which is provided on a metal wall of a package for mounting thereon a high-frequency element.
2. Description of the Related Art
In the prior art, it is generally known that a metal wall of a package for mounting thereon a high-frequency element is provided with a through hole into which a lead for transmitting a high frequency signal is inserted and hermetically sealed therein by means of a glass to control the characteristic impedance of the lead.
However, in a coaxial line assembly known in the prior art, since the lead inserted in the through hole is embraced with a glass having a high dielectric constant, it is difficult to efficiently transmit a high frequency signal due to a transmission loss of the dielectric material of the glass.